Toast bread for 2-3 min under broiler. Add 3-4 slices of cheese, followed by red onion, 2-3 slices tomato, 2 basil leaves, half of each steak, a handful of arugula and 1 tsp of balsamic vinegar per toast. Serve immediately and save leftover slices of bread for another purpose (they can be frozen for the next time you make this meal!)